Extension switch



Patented Mar. 2, 1937 UNITED STATES PATENT OFFICE SCIalma This invention relates to improvements in electrical circuit makers and breakers and associated appliances and more particularly to switches.

One of the main objects of the present invention is to provide a simple, efllcient and inexpensive device ior the distinct purpose of increasing the control of an electrical circuit from more than one location in such a manner that both controls need not be brought into iunctioning at the same time.

Another purpose of the present invention is to provide, in a device of the kind described a combination plug and socket unit having a local switch and having a cord extension carrying remote switch, the wiring connections between switches being such that any switch may control the circuit independently of other switches.

It is well known that the manner in which switches are now constructed for controlling the circuit on and oil! conditions of an electric device such as one or more lamp or lamps is to provide a main master switch for supplying ieed current to the conductors leading to a device or to the lamps, and to equip one or more of the individual lamps with a local switch, so thatwithout placing the master switch in circuit of! position, the local switch may open or close the circuit to the lamps independently of the master switch. In circuit with the series of lamps or with the electrical device may be .diflerent switches located at remote points from the lamps or device, and in some cases a separate local switch for each lamp or a switch controlling simultaneously all the lamps located adjacent to the switch; but none of the remote switches will be adapted to control the circuit on or of! conditions of the lamp circuit independently of the circuit ofl or on conditions of the local switch or switches; since ii the local switch has been placed in circuit of! position-it would be necessary to close the circuit to the lamps from this point, unless a remote switch directly was wired to close the lamp circuit as is the case oi the present invention.

A further object of my invention is to provide means capable of being connected in a lamp circuit or similar circuit which provides at the same time a local circuit control for the lamp circuit and anJndependent remote circuit control for the same circuit.

A still further object of the present invention consists in providing a cord attachment to an electrical circuit outlet which permits one or more remote switches connected to this cord attachment to control the electrical circuit remotely when desired. or locally by means of the usual or conventional switch carried by the electrical device associated with the cord attachment. In this way an existing circuit line obtaining current from outside wires may have a 5 line extension connected therewith, and, at the same time may receive a lamp or other electrical device connected in an electrical contact therewith, so that a local switch carried by the lamp and remote switches carried by the line exten- 1o sion may separately and selectively control the lamp circuit- Another object of the present invention is to provide an electrical means adapted to be plugged into a circuit outlet and having provision for 15 receiving itself an attachment cord or contact device of an electrical device, with a switch control to the circuit to this device, and in addition having provision for wiring a series or separate switches at some remote point from but in cir- 20 cult with the device electrical circuit, and in such a manner that if it is desired to open an electrical circuit leading to the attachment cord or to the electrical device which has already been closed by the first-named switch, it will not be 25 necessary to manipulate this last named switch to place it in circuit open position. The operator may operate any of the remote switches for opening the circuit to the electrical device.

with the above and other objects in view my invention consists in the combination, arrangement and details of construction disclosed in the drawing and specifications, and then more particularly pointed out in the appended claims.

Figure 1 is a diagrammatic view of a circuit 35 embodying my invention,

Figure 2 is a diagrammatic view of my invention,

Figure 3 is a diagrammatic view of my invention, 40

Figure 4 is a iragmental view, in side elevation of the parts of my invention, and

Figure 5 is a diagrammatic view of my invention showing some of the electrical principles in detail. 45

The details of my invention are disclosed in the drawing. In order to explain what now takes place when an electrical circuit, say to a lighting system iscontrolled, reference is made to Figure 2. Here the line wires l5, l8 conn ct 50 respectively to the lamps I1, and to point or contact E of a three way switch whose other points are designated C and D being connected by wire M. The movable switch element F is designed to sweep across the contact E and to connect 55 same with either contact point C or D. Wire H leads from wire M and connects with a fixed contact point A, designed to be engaged by the movable switch element B to which the wire G leads also to the lamps I. In this figure the circuit to the lamps is shown open since switch element B does not contact point A; no'matter which contact point, C or D the switch element F engages, it is evident that there will still be an open lamp circuit until switch element B is closed.

My invention consists of a combination plug and socket unit, of which the socket is designated III, the plug II. The inside construction of the unit may vary as to the manner of pro viding a three-way switch but by way of illustration Figure 1. discloses a circuit arrangement suitable to my invention. The usual socket contact I2 is provided designed to engage the outlet contact |4 when the plug is screwed home in the usual outlet. A nipple ll, see Figure 4, is provided upon the socket part of my unit, out of which leads an extension cord I 8 which connects to a distant switch device IS, the movable switch element of which is designated 28. The three points of the threeway switch of my invention are designated respectively 2|, 22 and 23, and a conductor 24 connects point 22 with the contact l3. A conductor P connects the plug and the socket parts 01' my invention, as is usual, in such cases. The movable switch element .22 associated with the two points 2| and 23' may be of any approved design of construction. The three contact points 01 the remote switch device I 9 connected to the line or cord |8 are designated respectively 23a, |2a and-2|a. A conductor 26 connects socket contact l2 with point I2a, conductor 21 connects point 23 with point 23a, while conductor 28 connects point 2| with point 2|a, it being understood that all three conductors 26, 21, and 28 may be connected together in the cord l8.

A four-way movable switch element 30 is pivoted conventionally so as to connect either the two contact points 3|, 32--33, 34 or else the points. 3|, 33-32, 34 oi. a four-way switch. In Figure 5 it will be seen that wire 21 connects point 2| of the-right-hand three-way switch to point 32 of the tour-way switch, wire 36 connects point 3| of the four-way switch to point 23a of the other three-way switch; wire 31 connects point 2 I11 of the left-hand three-way switch to point 34 of the four-way switch while wire 28 connects point 33 of the tour-way switch to the sired to close this circuit either switch element 28 or 29 of either of the two three-way switches may be placed to contact point 23 or point 2| (1, as the case may be. I do not confine myself to the exact details of construction.

What I desire to claim and seek protection on is as follows':

1. In combination an adapter unit having an attachment plug, a receptacle for receiving an electrical device and a three-way switch, an extension cord having one or more switches connected thereto and connected to selected contacts of said adapter, said switches and connections being so arranged as to provide selective control of said electrical device from any of said switches.

2. In combination an adapter unit having an attachment plug, a receptacle for receiving an electrical device and a switch, an extension cord having one or more switches connected thereto and connected to selected contacts of said adapter, said switches and connections being so arranged as to provide selective control of said electrical device from any of said switches.

3. In combination an adapter unit having means of connection to an electrical circuit, a means for receiving an electrical device and a switch, an extension line having one or more switches connected thereto and connected to selected contacts of said adapter, said switches and connections being so arranged as to provide se lective control of said electrical device from any of said switches.

DANIEL L. STAYTON. 

